This page is intended primarily for admins who already have Signalboost channels. If you need a channel, check out the Getting Started section. If you want to know more about why you should use Signalboost for your activist organizing work, check out our FAQ's.

Conceptual overview

A Signalboost channel is a phone number that keeps track of admins and subscribers. Any time an admin sends a message to the channel, it is interpreted as a command or a broadcast. If admins send a broadcast, all of the subscribers will see it, but Signalboost will route the broadcast so that it appears as if coming from the channel phone number.

What is a command?

A command is a word or phrase sent as a Signal message that Signalboost will interpret as an instruction. Some commands can only be used by admins. If you're unsure which command to use, the HELP command is a great place to start.

Signalboost currently supports English, Spanish, French, and German. To switch to your language of choice, type the name of the language into the channel. For example, if I want to switch my language to Spanish, I would send "ESPAÑOL" to the channel.

Disappearing Messages

By default, messages on Signalboost channels disappear after 1 week. However, admins and admins only can override the 1-week duration using the disappearing message timer in the top right hand corner of the Signal app. We recommend shortening the duration of disappearing message timer (usually to 1 day or 6 hours) if your broadcasts will contain sensitive information.



Lists the possible commands you can use.


Shows stats and briefly explains how Signalboost works.

Managing your channel

ADD / REMOVE +1-555-555-5555

Adds or removes +1-555-555-5555 as an admin of the channel. Any admins can remove or add any other admins.

RENAME new name

Renames channel to "new name"

Example: RENAME My Cool Signalboost Channel

DESCRIPTION description of channel

Adds or updates public description of channel.

Example: DESCRIPTION This is the _super cool activist_ signalboost channel! We'll use it to make announcements for the upcoming protest.


VOUCHING ON: turning vouching on means that an invite (1 by default) is required to join the channel. Both admins and subscribers can invite people to the channel using the INVITE command.

VOUCHING OFF: this is the default behavior of the channel; anyone can join by sending HELLO to the channel number.

VOUCHING ADMIN: this means that an invite from an *admin* is required to join the channel. If other people try to send invites, they will be prevented from doing so.

INVITE +1-555-555-5555

Invites +1-555-555-5555 to subscribe to the channel. Remember to preface the phone number with a + and country code!

Multiple invites can be sent by listing phone numbers separated by commas:

INVITE +1-555-555-5555, +1-333-333-3333


This changes the number of invites needed to join the channel; currently the vouch level must be between 1 and 10.

Example: VOUCH LEVEL 3

After executing this command, anyone who wants to join the channel will need 3 invites.

Managing a hotline


Enables or disables a hotline, which allows admins to receive anonymous messages from subscribers. Channel hotlines are off by default. If you're an admin, you'll know that a message coming in is a hotline message because it will have the following header:

[HOTLINE #3214]

If you decide to turn the hotline on:

  • Your subscribers' anonymity will be preserved when they message the hotline.
  • Depending on the number of people subscribed to your channel, the hotline can be noisy and increase the chances of spam/abuse.


Incoming hotline messages are followed by a hotline #:

[HOTLINE #3214]

Hello! We need a legal representative at jail support location XYZ.

In order to respond to a hotline message, type REPLY:

REPLY #3214 Okay, we are sending someone over!

And the subscriber you replied to will receive the following message:


Okay, we are sending someone over!

Other useful commands

PRIVATE good morning fellow admins!

Sends a private message to admins only (subscribers will not be able to see those messages).


Switches language to Spanish, French, or German. Language changes on Signalboost are user-specific, so if you change your language to Spanish other admins and subscribers' channels will be unaffected.


Leaves the channel. If you're an admin, you will lose your admin access to the channel but will still be able to subscribe as a subscriber. If you want to obtain admin access again, you will need to ask a current admin to add you using the ADD command.


Danger zone! This command permanently destroys the channel and all associated records. Importantly, it does not erase the message history from admin and subscribers phones until the duration of the disappearing message timer is up.